1. Technical Field
The present invention generally relates to an apparatus for delivering precise amounts of a gas or liquid in a quantifiable manner. In one embodiment of the present invention, the present invention is used to deliver special gas to a patient in a medical setting.
2. Description of the Related Art
It has been recently discovered that injecting certain types of gas into a patients"" lungs can greatly improve MRI images taken of the lungs. Hyperpolarized noble gasses such as Xenon 129 and Helium 3 work particularly well for this purpose. However, injecting the correct amount of these gases into a patient""s lungs in a magnetic resonance setting has proven difficult.
Therefore, what is needed is a device that can deliver a precise amount of a gas in a medical setting. The device should be compatible for use with a MRI device. Also, it would be advantageous for such a device to be constructed in a simple, reliable manner, using off-the-shelf components. In addition, the design for such a device should be adaptable for use wherever the need to deliver a measured amount of a gas or liquid exists.
The present invention uses a ventilator and a series of valves to deliver a special gas to a patient. Attached to a tube extending from the ventilator to the patient is a first valve. The valve alternately connects the patient to the ventilator then to a supply of the special gas. Between the first valve and the supply of gas is a second valve, which controls the pressure between the first valve and the second valve caused by the special gas. The supply of special gas is connected to the second valve. A flow regulator controls the rate at which the special gas enters the patient. A controller is also interfaced to the ventilator and valves to synchronize the opening and closing of the valves and the operation of the ventilator with the patient""s respiratory cycles. Detection equipment is connected to the controller and is capable of signaling the controller based upon the respiratory cycles of a patient. In this way, the detection equipment can control the position of the first valve in response to a patient""s respiratory cycle.